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Date: Tue, 3 Jun 2014 10:31:11 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: David Herrmann <dh.herrmann@gmail.com>
Cc: Jan Kara <jack@suse.cz>, Minchan Kim <minchan@kernel.org>,
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Subject: Re: [PATCH v2 0/3] File Sealing & memfd_create()
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On Mon, Jun 02, 2014 at 06:04:02PM +0200, David Herrmann wrote:
> Correct, the problem is not accounting for pinned-pages, but waiting
> for them to get released. Furthermore, Peter's patches make VM_PINNED
> an optional feature, so we'd still miss all the short-term GUP users.
> Sadly, that means we cannot even use it to test for pending GUP users.

Right, I'm not bothered about temporary pins, they'll go away quickly
and generally not bother reclaim and the like (much). The thing I
'worry' about is the persistent pins, which have unbounded life spans.

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